Make Sure Your HVAC Technician Performs Load Calculations Before You Buy a New System

Buying a new heating or cooling system for your Chicagoland home is among the greatest challenges that a homeowner will face, and considering the short-term investment, ongoing operating costs and your comfort, you’ll want to insist that the technicians perform load calculations first. These calculations are essential to selecting the right size system for your home. Avoid a technician who simply goes by the size of your existing equipment or who wants to do a simple calculation based on your home’s square footage.

What’s Involved in Sizing a System?

Conditions inside your home may have changed since the time your current system was installed. If you or a previous owner improved its energy efficiency, you may be able to use a smaller system. Or your system very well could have been oversized to begin with, since this used to be the common practice. Factors considered in heating or cooling load calculations include:

• The level of insulation in the attic.
• Amount of air infiltration throughout your home.
• The number, size and quality of your windows.
• The layout of your home, including number of floors.
• Preferred indoor temperatures.
• Number of household members and their ages.
• How much heat you produce indoors.
• Landscaping factors.

Contractors use Manual J software to run the load calculations. Once your home’s heating or cooling load is calculated, the size of the needed system can be determined. The related Manual D figures the size and design for the ductwork. Misjudging the size for the system and the ductwork will cost you in comfort, energy bills and the system’s durability.

An HVAC system that’s too large will run in short spurts that drive up energy costs and increase wear on all the parts. In the winter, a furnace that’s oversized won’t circulate the air long enough to warm the rooms farther from the thermostat, and it won’t filter out as many airborne particulates. A cooling system that’s too big will short cycle as well, leaving humidity behind.

The results of the load calculation could also help you improve your home’s energy efficiency. The contractor may also recommend an energy audit if he or she finds significant problems with insulation or air infiltration inside your home. Sealing air leaks and adding insulation are affordable projects that may reduce the equipment size you need.

To learn more about load calculations, contact the pros at Climate Master Mechanical Contractors. We’ve provided quality HVAC services for Chicagoland homeowners for more than 20 years.

Image Provided by Shutterstock.com